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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a>
<FONT color="green">003</FONT>     * contributor license agreements.  See the NOTICE file distributed with<a name="line.3"></a>
<FONT color="green">004</FONT>     * this work for additional information regarding copyright ownership.<a name="line.4"></a>
<FONT color="green">005</FONT>     * The ASF licenses this file to You under the Apache License, Version 2.0<a name="line.5"></a>
<FONT color="green">006</FONT>     * (the "License"); you may not use this file except in compliance with<a name="line.6"></a>
<FONT color="green">007</FONT>     * the License.  You may obtain a copy of the License at<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     *      http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a>
<FONT color="green">012</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a>
<FONT color="green">013</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a>
<FONT color="green">014</FONT>     * See the License for the specific language governing permissions and<a name="line.14"></a>
<FONT color="green">015</FONT>     * limitations under the License.<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    package org.apache.commons.net.util;<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    import java.util.regex.Matcher;<a name="line.19"></a>
<FONT color="green">020</FONT>    import java.util.regex.Pattern;<a name="line.20"></a>
<FONT color="green">021</FONT>    <a name="line.21"></a>
<FONT color="green">022</FONT>    /**<a name="line.22"></a>
<FONT color="green">023</FONT>     * A class that performs some subnet calculations given a network address and a subnet mask. <a name="line.23"></a>
<FONT color="green">024</FONT>     * @see http://www.faqs.org/rfcs/rfc1519.html<a name="line.24"></a>
<FONT color="green">025</FONT>     * @author &lt;rwinston@apache.org&gt;<a name="line.25"></a>
<FONT color="green">026</FONT>     * @since 2.0<a name="line.26"></a>
<FONT color="green">027</FONT>     */<a name="line.27"></a>
<FONT color="green">028</FONT>    public class SubnetUtils {<a name="line.28"></a>
<FONT color="green">029</FONT>    <a name="line.29"></a>
<FONT color="green">030</FONT>        private static final String IP_ADDRESS = "(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})";<a name="line.30"></a>
<FONT color="green">031</FONT>        private static final String SLASH_FORMAT = IP_ADDRESS + "/(\\d{1,3})";<a name="line.31"></a>
<FONT color="green">032</FONT>        private static final Pattern addressPattern = Pattern.compile(IP_ADDRESS);<a name="line.32"></a>
<FONT color="green">033</FONT>        private static final Pattern cidrPattern = Pattern.compile(SLASH_FORMAT);<a name="line.33"></a>
<FONT color="green">034</FONT>        private static final int NBITS = 32;<a name="line.34"></a>
<FONT color="green">035</FONT>    <a name="line.35"></a>
<FONT color="green">036</FONT>        private int netmask = 0;<a name="line.36"></a>
<FONT color="green">037</FONT>        private int address = 0;<a name="line.37"></a>
<FONT color="green">038</FONT>        private int network = 0;<a name="line.38"></a>
<FONT color="green">039</FONT>        private int broadcast = 0;<a name="line.39"></a>
<FONT color="green">040</FONT>    <a name="line.40"></a>
<FONT color="green">041</FONT>        /**<a name="line.41"></a>
<FONT color="green">042</FONT>         * Constructor that takes a CIDR-notation string, e.g. "192.168.0.1/16"<a name="line.42"></a>
<FONT color="green">043</FONT>         * @param cidrNotation A CIDR-notation string, e.g. "192.168.0.1/16"<a name="line.43"></a>
<FONT color="green">044</FONT>         */<a name="line.44"></a>
<FONT color="green">045</FONT>        public SubnetUtils(String cidrNotation) {<a name="line.45"></a>
<FONT color="green">046</FONT>            calculate(cidrNotation);<a name="line.46"></a>
<FONT color="green">047</FONT>        }<a name="line.47"></a>
<FONT color="green">048</FONT>    <a name="line.48"></a>
<FONT color="green">049</FONT>        /**<a name="line.49"></a>
<FONT color="green">050</FONT>         * Constructor that takes two dotted decimal addresses. <a name="line.50"></a>
<FONT color="green">051</FONT>         * @param address An IP address, e.g. "192.168.0.1"<a name="line.51"></a>
<FONT color="green">052</FONT>         * @param mask A dotted decimal netmask e.g. "255.255.0.0"<a name="line.52"></a>
<FONT color="green">053</FONT>         */<a name="line.53"></a>
<FONT color="green">054</FONT>        public SubnetUtils(String address, String mask) {<a name="line.54"></a>
<FONT color="green">055</FONT>            calculate(toCidrNotation(address, mask));<a name="line.55"></a>
<FONT color="green">056</FONT>        }<a name="line.56"></a>
<FONT color="green">057</FONT>    <a name="line.57"></a>
<FONT color="green">058</FONT>        /**<a name="line.58"></a>
<FONT color="green">059</FONT>         * Convenience container for subnet summary information.<a name="line.59"></a>
<FONT color="green">060</FONT>         *<a name="line.60"></a>
<FONT color="green">061</FONT>         */<a name="line.61"></a>
<FONT color="green">062</FONT>        public final class SubnetInfo {<a name="line.62"></a>
<FONT color="green">063</FONT>            private SubnetInfo() {}<a name="line.63"></a>
<FONT color="green">064</FONT>    <a name="line.64"></a>
<FONT color="green">065</FONT>            private int netmask()       { return netmask; }<a name="line.65"></a>
<FONT color="green">066</FONT>            private int network()       { return network; }<a name="line.66"></a>
<FONT color="green">067</FONT>            private int address()       { return address; }<a name="line.67"></a>
<FONT color="green">068</FONT>            private int broadcast()     { return broadcast; }<a name="line.68"></a>
<FONT color="green">069</FONT>            private int low()           { return network() + 1; }<a name="line.69"></a>
<FONT color="green">070</FONT>            private int high()          { return broadcast() - 1; }<a name="line.70"></a>
<FONT color="green">071</FONT>    <a name="line.71"></a>
<FONT color="green">072</FONT>            public boolean isInRange(String address)    { return isInRange(toInteger(address)); }<a name="line.72"></a>
<FONT color="green">073</FONT>            private boolean isInRange(int address)      { return ((address-low()) &lt;= (high()-low())); }<a name="line.73"></a>
<FONT color="green">074</FONT>    <a name="line.74"></a>
<FONT color="green">075</FONT>            public String getBroadcastAddress()         { return format(toArray(broadcast())); }<a name="line.75"></a>
<FONT color="green">076</FONT>            public String getNetworkAddress()           { return format(toArray(network())); }<a name="line.76"></a>
<FONT color="green">077</FONT>            public String getNetmask()                  { return format(toArray(netmask())); }<a name="line.77"></a>
<FONT color="green">078</FONT>            public String getAddress()                  { return format(toArray(address())); }<a name="line.78"></a>
<FONT color="green">079</FONT>            public String getLowAddress()               { return format(toArray(low())); }<a name="line.79"></a>
<FONT color="green">080</FONT>            public String getHighAddress()              { return format(toArray(high())); }<a name="line.80"></a>
<FONT color="green">081</FONT>            public int getAddressCount()                { return (broadcast() - low()); }<a name="line.81"></a>
<FONT color="green">082</FONT>    <a name="line.82"></a>
<FONT color="green">083</FONT>            public int asInteger(String address)        { return toInteger(address); }<a name="line.83"></a>
<FONT color="green">084</FONT>            <a name="line.84"></a>
<FONT color="green">085</FONT>            public String getCidrSignature() { <a name="line.85"></a>
<FONT color="green">086</FONT>                return toCidrNotation(<a name="line.86"></a>
<FONT color="green">087</FONT>                        format(toArray(address())), <a name="line.87"></a>
<FONT color="green">088</FONT>                        format(toArray(netmask()))<a name="line.88"></a>
<FONT color="green">089</FONT>                );<a name="line.89"></a>
<FONT color="green">090</FONT>            }<a name="line.90"></a>
<FONT color="green">091</FONT>            <a name="line.91"></a>
<FONT color="green">092</FONT>            public String[] getAllAddresses() { <a name="line.92"></a>
<FONT color="green">093</FONT>                String[] addresses = new String[getAddressCount()];<a name="line.93"></a>
<FONT color="green">094</FONT>                for (int add = low(), j=0; add &lt;= high(); ++add, ++j) {<a name="line.94"></a>
<FONT color="green">095</FONT>                    addresses[j] = format(toArray(add));<a name="line.95"></a>
<FONT color="green">096</FONT>                }<a name="line.96"></a>
<FONT color="green">097</FONT>                return addresses;<a name="line.97"></a>
<FONT color="green">098</FONT>            }<a name="line.98"></a>
<FONT color="green">099</FONT>        }<a name="line.99"></a>
<FONT color="green">100</FONT>    <a name="line.100"></a>
<FONT color="green">101</FONT>        /**<a name="line.101"></a>
<FONT color="green">102</FONT>         * Return a {@link SubnetInfo} instance that contains subnet-specific statistics<a name="line.102"></a>
<FONT color="green">103</FONT>         * @return<a name="line.103"></a>
<FONT color="green">104</FONT>         */<a name="line.104"></a>
<FONT color="green">105</FONT>        public final SubnetInfo getInfo() { return new SubnetInfo(); }<a name="line.105"></a>
<FONT color="green">106</FONT>    <a name="line.106"></a>
<FONT color="green">107</FONT>        /*<a name="line.107"></a>
<FONT color="green">108</FONT>         * Initialize the internal fields from the supplied CIDR mask<a name="line.108"></a>
<FONT color="green">109</FONT>         */<a name="line.109"></a>
<FONT color="green">110</FONT>        private void calculate(String mask) {<a name="line.110"></a>
<FONT color="green">111</FONT>            Matcher matcher = cidrPattern.matcher(mask);<a name="line.111"></a>
<FONT color="green">112</FONT>    <a name="line.112"></a>
<FONT color="green">113</FONT>            if (matcher.matches()) {<a name="line.113"></a>
<FONT color="green">114</FONT>                address = matchAddress(matcher);<a name="line.114"></a>
<FONT color="green">115</FONT>    <a name="line.115"></a>
<FONT color="green">116</FONT>                /* Create a binary netmask from the number of bits specification /x */<a name="line.116"></a>
<FONT color="green">117</FONT>                int cidrPart = rangeCheck(Integer.parseInt(matcher.group(5)), 0, NBITS-1);<a name="line.117"></a>
<FONT color="green">118</FONT>                for (int j = 0; j &lt; cidrPart; ++j) {<a name="line.118"></a>
<FONT color="green">119</FONT>                    netmask |= (1 &lt;&lt; 31-j);<a name="line.119"></a>
<FONT color="green">120</FONT>                }<a name="line.120"></a>
<FONT color="green">121</FONT>    <a name="line.121"></a>
<FONT color="green">122</FONT>                /* Calculate base network address */<a name="line.122"></a>
<FONT color="green">123</FONT>                network = (address &amp; netmask);<a name="line.123"></a>
<FONT color="green">124</FONT>    <a name="line.124"></a>
<FONT color="green">125</FONT>                /* Calculate broadcast address */<a name="line.125"></a>
<FONT color="green">126</FONT>                broadcast = network | ~(netmask);<a name="line.126"></a>
<FONT color="green">127</FONT>            }<a name="line.127"></a>
<FONT color="green">128</FONT>            else <a name="line.128"></a>
<FONT color="green">129</FONT>                throw new IllegalArgumentException("Could not parse [" + mask + "]");<a name="line.129"></a>
<FONT color="green">130</FONT>        }<a name="line.130"></a>
<FONT color="green">131</FONT>    <a name="line.131"></a>
<FONT color="green">132</FONT>        /*<a name="line.132"></a>
<FONT color="green">133</FONT>         * Convert a dotted decimal format address to a packed integer format<a name="line.133"></a>
<FONT color="green">134</FONT>         */<a name="line.134"></a>
<FONT color="green">135</FONT>        private int toInteger(String address) {<a name="line.135"></a>
<FONT color="green">136</FONT>            Matcher matcher = addressPattern.matcher(address);<a name="line.136"></a>
<FONT color="green">137</FONT>            if (matcher.matches()) {<a name="line.137"></a>
<FONT color="green">138</FONT>                return matchAddress(matcher);<a name="line.138"></a>
<FONT color="green">139</FONT>            }<a name="line.139"></a>
<FONT color="green">140</FONT>            else<a name="line.140"></a>
<FONT color="green">141</FONT>                throw new IllegalArgumentException("Could not parse [" + address + "]");<a name="line.141"></a>
<FONT color="green">142</FONT>        }<a name="line.142"></a>
<FONT color="green">143</FONT>    <a name="line.143"></a>
<FONT color="green">144</FONT>        /*<a name="line.144"></a>
<FONT color="green">145</FONT>         * Convenience method to extract the components of a dotted decimal address and <a name="line.145"></a>
<FONT color="green">146</FONT>         * pack into an integer using a regex match<a name="line.146"></a>
<FONT color="green">147</FONT>         */<a name="line.147"></a>
<FONT color="green">148</FONT>        private int matchAddress(Matcher matcher) {<a name="line.148"></a>
<FONT color="green">149</FONT>            int addr = 0;<a name="line.149"></a>
<FONT color="green">150</FONT>            for (int i = 1; i &lt;= 4; ++i) { <a name="line.150"></a>
<FONT color="green">151</FONT>                int n = (rangeCheck(Integer.parseInt(matcher.group(i)), 0, 255));<a name="line.151"></a>
<FONT color="green">152</FONT>                addr |= ((n &amp; 0xff) &lt;&lt; 8*(4-i));<a name="line.152"></a>
<FONT color="green">153</FONT>            }<a name="line.153"></a>
<FONT color="green">154</FONT>            return addr;<a name="line.154"></a>
<FONT color="green">155</FONT>        }<a name="line.155"></a>
<FONT color="green">156</FONT>    <a name="line.156"></a>
<FONT color="green">157</FONT>        /*<a name="line.157"></a>
<FONT color="green">158</FONT>         * Convert a packed integer address into a 4-element array<a name="line.158"></a>
<FONT color="green">159</FONT>         */<a name="line.159"></a>
<FONT color="green">160</FONT>        private int[] toArray(int val) {<a name="line.160"></a>
<FONT color="green">161</FONT>            int ret[] = new int[4];<a name="line.161"></a>
<FONT color="green">162</FONT>            for (int j = 3; j &gt;= 0; --j)<a name="line.162"></a>
<FONT color="green">163</FONT>                ret[j] |= ((val &gt;&gt;&gt; 8*(3-j)) &amp; (0xff));<a name="line.163"></a>
<FONT color="green">164</FONT>            return ret;<a name="line.164"></a>
<FONT color="green">165</FONT>        }<a name="line.165"></a>
<FONT color="green">166</FONT>    <a name="line.166"></a>
<FONT color="green">167</FONT>        /*<a name="line.167"></a>
<FONT color="green">168</FONT>         * Convert a 4-element array into dotted decimal format<a name="line.168"></a>
<FONT color="green">169</FONT>         */<a name="line.169"></a>
<FONT color="green">170</FONT>        private String format(int[] octets) {<a name="line.170"></a>
<FONT color="green">171</FONT>            StringBuilder str = new StringBuilder();<a name="line.171"></a>
<FONT color="green">172</FONT>            for (int i =0; i &lt; octets.length; ++i){<a name="line.172"></a>
<FONT color="green">173</FONT>                str.append(octets[i]);<a name="line.173"></a>
<FONT color="green">174</FONT>                if (i != octets.length - 1) {<a name="line.174"></a>
<FONT color="green">175</FONT>                    str.append("."); <a name="line.175"></a>
<FONT color="green">176</FONT>                }<a name="line.176"></a>
<FONT color="green">177</FONT>            }<a name="line.177"></a>
<FONT color="green">178</FONT>            return str.toString();<a name="line.178"></a>
<FONT color="green">179</FONT>        }<a name="line.179"></a>
<FONT color="green">180</FONT>    <a name="line.180"></a>
<FONT color="green">181</FONT>        /*<a name="line.181"></a>
<FONT color="green">182</FONT>         * Convenience function to check integer boundaries<a name="line.182"></a>
<FONT color="green">183</FONT>         */<a name="line.183"></a>
<FONT color="green">184</FONT>        private int rangeCheck(int value, int begin, int end) {<a name="line.184"></a>
<FONT color="green">185</FONT>            if (value &gt;= begin &amp;&amp; value &lt;= end)<a name="line.185"></a>
<FONT color="green">186</FONT>                return value;<a name="line.186"></a>
<FONT color="green">187</FONT>    <a name="line.187"></a>
<FONT color="green">188</FONT>            throw new IllegalArgumentException("Value out of range: [" + value + "]");<a name="line.188"></a>
<FONT color="green">189</FONT>        }<a name="line.189"></a>
<FONT color="green">190</FONT>    <a name="line.190"></a>
<FONT color="green">191</FONT>        /*<a name="line.191"></a>
<FONT color="green">192</FONT>         * Count the number of 1-bits in a 32-bit integer using a divide-and-conquer strategy<a name="line.192"></a>
<FONT color="green">193</FONT>         * see Hacker's Delight section 5.1 <a name="line.193"></a>
<FONT color="green">194</FONT>         */<a name="line.194"></a>
<FONT color="green">195</FONT>        int pop(int x) {<a name="line.195"></a>
<FONT color="green">196</FONT>            x = x - ((x &gt;&gt;&gt; 1) &amp; 0x55555555); <a name="line.196"></a>
<FONT color="green">197</FONT>            x = (x &amp; 0x33333333) + ((x &gt;&gt;&gt; 2) &amp; 0x33333333); <a name="line.197"></a>
<FONT color="green">198</FONT>            x = (x + (x &gt;&gt;&gt; 4)) &amp; 0x0F0F0F0F; <a name="line.198"></a>
<FONT color="green">199</FONT>            x = x + (x &gt;&gt;&gt; 8); <a name="line.199"></a>
<FONT color="green">200</FONT>            x = x + (x &gt;&gt;&gt; 16); <a name="line.200"></a>
<FONT color="green">201</FONT>            return x &amp; 0x0000003F; <a name="line.201"></a>
<FONT color="green">202</FONT>        } <a name="line.202"></a>
<FONT color="green">203</FONT>    <a name="line.203"></a>
<FONT color="green">204</FONT>        /* Convert two dotted decimal addresses to a single xxx.xxx.xxx.xxx/yy format<a name="line.204"></a>
<FONT color="green">205</FONT>         * by counting the 1-bit population in the mask address. (It may be better to count <a name="line.205"></a>
<FONT color="green">206</FONT>         * NBITS-#trailing zeroes for this case)<a name="line.206"></a>
<FONT color="green">207</FONT>         */<a name="line.207"></a>
<FONT color="green">208</FONT>        private String toCidrNotation(String addr, String mask) {<a name="line.208"></a>
<FONT color="green">209</FONT>            return addr + "/" + pop(toInteger(mask));<a name="line.209"></a>
<FONT color="green">210</FONT>        }<a name="line.210"></a>
<FONT color="green">211</FONT>    }<a name="line.211"></a>




























































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